1. Technical Field
Embodiments of the present disclosure relate to signal processing, and more particularly to systems, and devices and a method of multipath compensation for digital pre-distortion linearization.
2. Description of Related Art
In wireless communication, a multi carrier signal is transmitted using a power amplifier (PA). Radio transmitter amplifiers in most telecommunications systems are required to be “linear”, which means accurately reproducing the input signal. An amplifier that compresses input signals or has a non-linear input/output relationship causes the output signal to splatter onto adjacent radio frequencies. This causes interference to other radio channels.
Predistortion is a technique used to improve the linearity of radio transmitter amplifiers. The multi carrier PA (MCPA) transmission should transmit the signal at a very high efficiency while maintaining acceptable signal quality and a high adjacent channel power ratio (ACPR) to meet the spectral emissions mask (SEM) requirements.
The transmission system would employ a digital pre-distortion (DPD) linearizer to suppress the intermodulation distortion to achieve high ACPR. To achieve this goal, the DPD linearizer compares observed transmission signals with observed feedback signals and derives the optimum solution that is applied to the DPD function to reverse the effects of the PA non-linearity, and improve the ACPR.
In addition to PA distortion, however, multipath distortions also exist along a transmission path. These linear distortions may degrade the DPD linearization performance.